loplugin:external (clang-cl)

Including:

* expanding STDAPI to its definition (as per
<https://msdn.microsoft.com/library/ms686631(vs.85).aspx> "STDAPI"), to add
__declspec(dllexport) into its middle, in
extensions/source/activex/so_activex.cxx; as discussed in the comments at
<https://gerrit.libreoffice.org/#/c/60691/> "Get rid of Windows .def files in
setup_native, use __declspec(dllexport)", having a function both listed in a
.def file EXPORTS and marking it dllexport is OK, and the latter helps the
heuristics of loplugin:external; however, the relevant functions in
extensions/source/activex/so_activex.cxx probably don't even need to be
exported in the first place?

* follow-up loplugin:salcall in sal/osl/w32/file-impl.hxx

Change-Id: Ida6e17eba19cfa3d7e5c72dda57409005c0a0191
Reviewed-on: https://gerrit.libreoffice.org/60938
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

1 files changed, 36 insertions, 10 deletions

diff --git a/compilerplugins/clang/external.cxx b/compilerplugins/clang/external.cxx
index bb4bcbf36d08..d30b8cba3c5f 100644
--- a/compilerplugins/clang/external.cxx
+++ b/compilerplugins/clang/external.cxx
@@ -126,20 +126,29 @@ public:
         {
             return true;
         }
-        if (decl->isMain())
+        if (decl->isMain() || decl->isMSVCRTEntryPoint())
         {
             return true;
         }
+        if (hasCLanguageLinkageType(decl)
+            && loplugin::DeclCheck(decl).Function("_DllMainCRTStartup").GlobalNamespace())
+        {
+            return true;
+        }
+        // If the function definition is explicit marked SAL_DLLPUBLIC_EXPORT or similar, then
+        // assume that it needs to be present (e.g., only called via dlopen, or a backwards-
+        // compatibility stub like in sal/osl/all/compat.cxx):
         if (auto const attr = decl->getAttr<VisibilityAttr>())
         {
             if (attr->getVisibility() == VisibilityAttr::Default)
             {
-                // If the function definition has explicit default visibility, then assume that it
-                // needs to be present (e.g., only called via dlopen, or a backwards-compatibility
-                // stub like in sal/osl/all/compat.cxx):
                 return true;
             }
         }
+        else if (decl->hasAttr<DLLExportAttr>())
+        {
+            return true;
+        }
         auto const canon = decl->getCanonicalDecl();
         if (hasCLanguageLinkageType(canon)
             && (canon->hasAttr<ConstructorAttr>() || canon->hasAttr<DestructorAttr>()))
@@ -177,6 +186,10 @@ public:
         {
             return true;
         }
+        if (loplugin::DeclCheck(decl).Var("_pRawDllMain").GlobalNamespace())
+        {
+            return true;
+        }
         return handleDeclaration(decl);
     }
 
@@ -261,14 +274,27 @@ private:
                 return true;
             }
         }
-        if (compiler.getSourceManager().isMacroBodyExpansion(decl->getLocation())
-            && (Lexer::getImmediateMacroName(decl->getLocation(), compiler.getSourceManager(),
+        if (compiler.getSourceManager().isMacroBodyExpansion(decl->getLocation()))
+        {
+            if (Lexer::getImmediateMacroName(decl->getLocation(), compiler.getSourceManager(),
                                              compiler.getLangOpts())
-                == "MDDS_MTV_DEFINE_ELEMENT_CALLBACKS"))
+                == "MDDS_MTV_DEFINE_ELEMENT_CALLBACKS")
+            {
+                // Even wrapping in an unnamed namespace or sneaking "static" into the macro
+                // wouldn't help, as then some of the functions it defines would be flagged as
+                // unused:
+                return true;
+            }
+        }
+        else if (compiler.getSourceManager().isMacroArgExpansion(decl->getLocation()))
         {
-            // Even wrapping in an unnamed namespace or sneaking "static" into the macro wouldn't
-            // help, as then some of the functions it defines would be flagged as unused:
-            return true;
+            if (Lexer::getImmediateMacroName(decl->getLocation(), compiler.getSourceManager(),
+                                             compiler.getLangOpts())
+                == "DEFINE_GUID")
+            {
+                // Windows, guiddef.h:
+                return true;
+            }
         }
         TypedefNameDecl const* typedefed = nullptr;
         if (auto const d = dyn_cast<TagDecl>(decl))